Bill Nye's father had been held prisoner of war in Japan, where in the night's dark skies he grew fascinated by astronomy and in daylight he used a handmade sundial to determine the prison camp's latitudinal location. When the war ended, the elder Nye went into the sundial business, and passed on his love of science to his son.

One of young Nye's earliest memories is of spending hours watching bumblebees in flight. Later, playing with a rubber-band-and-balsa-wood model airplane, he figured out how to make it turn in flight. He was always fascinated by aeronautics, physics, and space exploration, and in high school he earned extra money tutoring other kids in math and science. As a student at Cornell, Nye took the astronomy course taught by Carl Sagan, and after graduation he worked as a mechanical engineer, designing flight control systems for the aerospace giant Boeing.

Once ensconced in Boeing's Seattle offices, he became pals with Ross Shafer, a neighbor who did stand-up comedy and worked as a disc jockey on a rock'n'roll radio station. Nye began hamming up his naturally nerdy personality for comedy bits on Shafer's radio show in the early 1980s, and when Shafer was given a local TV talk-and-comedy show in 1984 called Almost Live, Nye tagged along, and his schtick was even funnier with visuals.

Nye left Boeing and worked in high-tech jobs at a few other local companies, until 1986, when the Challenger space shuttle exploded, killing Christa McAuliffe and everyone else aboard. Nye had never worked in the space program, but as he read articles in technical journals about the mistakes that led to that disaster, he saw reflections of his own career. "I could tell that I was working for people with the same management style as those who had let it happen," Nye has said.

He quit his job, and instead pursued triple careers as an engineering consultant, a stand-up comic, and as "Bill Nye, the science guy" on Almost Live. In 1988, Shafer left Seattle for Hollywood, which turned out to be Nye's big break -- without its host, Shafer's talk show was retooled without the talk, as all-comedy, leaving a larger role for Nye's increasingly popular science segments. When Hollywood called for Nye in 1992, he had to pack 13 local Emmys.

On the cartoonization of Back to the Future, Nye appeared in live-action segments as Christopher Lloyd's science sidekick. His Bill Nye the Science Guy earned five more Emmys for Nye, delighting kids and enlightening adults from 1992-98 on PBS, where it still lives in reruns on many stations. The show has also aired on The Disney Channel and MTV's Noggin Television. His later series, The Eyes of Nye, targeted a more grown-up demographic. He appeared as the know-it-all expert on Comedy Central's BattleBots machines-in-combat series, and he received on-screen credit as science consultant for Disney's Flubber in 1997, starring Robin Williams.

Nye is also an inventor, with patents or patents pending for a magnifying lens made of water, a better ballet shoe, an advanced abacus, and a device that analyzes baseball-pitching techniques. Like his father, Nye is a sundial enthusiast, and it was his idea to equip the Mars Exploration Rovers with sundials. He serves on the Board of Directors at The Planetary Society, and is now a professor at Cornell University, where he teaches in the same classroom where he was taught by Sagan.

He loves old fashioned swing music, and is married to oboe and English Horn player Blair Tindall. She is the author of Mozart in the Jungle: Sex, Drugs, and Classical Music, has written about classical music for the New York Times, and played for the soundtrack of Mr. & Mrs. Bridge, Mad Dog and Glory, and Spike Lee's Malcolm X, where she performed an extended oboe solo.